(a) Field of the Invention
The invention relates to enzymatic cleaning compositions and methods for using them. Particularly the invention relates to cleaning compositions comprising a surfactant and a cutinase enzyme.
(b) Background Information
A wide variety of enzymes are well known for use in cleaning compositions. The use of B. subtilisins and B. licheniformis protease in commercial preparations is common. Other enzymes have also been used in commercial cleaning compositions such as, for example, U.S. Pat. No. 4,011,169, and British Patent No. 1,293,613. Also a comprehensive review article of lipases in cleaning compositions can be found in Journal of Applied Biochemistry, 2:218-229 (1980) in an article entitled "Lipases as Detergent Components". Lipolytic detergent additives are also known from e.g., British Patent Specification No. 1,293,613 and Canadian Patent No. 835,343.
U.S. Pat. No. 3,950,277 and British Patent Specification No. 1,442,418 disclose lipase enzymes combined with an activator and calcium and/or magnesium ions, respectively, which are utilized to pre-soak soiled fabrics and to remove triglyceride stains and soils from polyester or polyester/cotton fabric blends, respectively. Suitable microbial lipases for use therein (apart from animal and plant derived lipases) are said to be those derived from Pseudomonas, Aspergillus, Pneumococcus, Staphylococcus, and Staphylococcus toxins, Mycobacterium tuberculosis, Mycotorula lipolytica, and Sclerotinia.
British Patent Specification No. 1,372,034 discloses a detergent composition comprising a bacterial lipase produced by Pseudomonas stutzeri strain ATCC 19154. Furthermore, it is recommended that the preferred lipolytic enzymes should have a pH optimum between 6 and 10, and should be active in said range, preferably between 7 and 9. Around 1970, this presumed Pseudomonas stutzeri strain was reclassified as Pseudomonas aeruginosa, as appears for example from the ATCC catalogues.
European Patent Application EP-A-No. 0130064 discloses an enzymatic detergent additive comprising a lipase isolated from Fusarium oxysporum with an alleged higher lipolytic cleaning efficiency than conventional lipases.
In European Patent Application No. 0214761, enzymatic detergent additives are described as the active component including a microbially produced lipase from a strain of Pseudomonas cepacia. The lipases described therein are claimed to be superior to the lipolytic detergent action of the prior art, especially at low temperature washing processes (around 60.degree. C. and below).
In PCT Patent Application No. 87/00859 other novel lipolytic enzymes are described as having an optimal pH in the range of 8-10.5 at a temperature of 60.degree. C. or less from bacterial strains selected from Pseudomonas pseudoalcaligenes, P. stutzeri and Acinetobacter calcoaceticus. These enzymes are described as particularly effective at low temperatures; i.e., 40.degree. C. or lower and effective in both liquid and solid detergent compositions.
Also in U.S. Pat. No. 3,950,277, it is described in general terms that lipases from Pseudomonas are suited as agents for removal of oily stains from fabrics, if used together with a special group of lipase activators. The art cited does not, however, cover cutinase enzymes from Pseudomonas or any other microbial source. However, prior art enzymes for use in cleaning compositions, while effective on many proteins and lipids, are not completely effective against all stains commonly found in laundry and other cleaning applications. Further, many lipases are not stable at pH 8-11 where most cleaning compositions are used. Even further, most enzymes for use in cleaning compositions are not very stable, if at all, under oxidative conditions or in the presence of other enzymes such as proteases.